There is a range of contributing factors for developing depression. These factors can be biological– brain chemistry, genes and personality traits. Or they can be life events – such as trauma and long term stress; or a combination of these factors. Read more about the causes of depression.

Seasonal affective disorder (SAD) is more common in the northern hemisphere (in places with less sunlight). As SAD is thought to be connected to light exposure, it has a marked seasonal pattern. Depression and mood issues occur during winter months, and ease off in spring and summer.

Pre-menstrual dysphoric disorder (PMDD) (also known as severe premenstrual syndrome). Symptoms are so severe they interfere with how a woman can operate in daily life, such as at work and in her close relationships.

Bipolar disorder is sometimes included as a depression. Read more about bipolar disorder.

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Educating yourself about mental illness is the foundation of providing support.